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05-04-2012, 08:24 PM   #1
CJBrewVT
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Feb 2011
Rutland, VT
Posts: 67
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My understanding is that AC fluctuates and can vary slightly. If a 2000 watt heater for 120 volts pulls 16.6 amps, does it pull more amps to maintain watts if the voltage drops to say 110 volts?

Do some of you run 2000w on a 20 amp circuit? It's close to the 80% threshold.

05-04-2012, 08:42 PM   #2
passedpawn
Waste Allocation Load Lifter - Earth Class

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Apr 2009
☼ Clearwater, FL ☼
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No. Elements are fixed resistance, so if you drop the voltage the current will drop as well.

Use I = V/R to find the current at any voltage (I = Amps, V = the RMS voltage, or say 110).

For your element, the fixed resistance of the element, R, is 7.2 ohms. (R = V^2/W = 120^2 / 2000 = 7.2)

So, @ 110V, the current is I = V/R = 110/7.2 = 15.3A
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05-09-2012, 12:57 AM   #3
CJBrewVT
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Feb 2011
Rutland, VT
Posts: 67
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Thank you! Ordered a 2000w element. Can't wait to get it all together.